Anyone with a lens needing re-cementing might also consider Mark Hansen at Classic Camera Repair (www.ZeissIkonRolleiRepair.com). He just re-cemented the front cell of my ancient uncoated 11 3/4-inch f8 Conley Symmetrical lens (a re-badged Wollensak Versar) and checked it out with a collimator. He did a great job on the lens, and I am pleased with the result. He said he liked working on old, interesting lenses.